It’s the soup, not the noodles, that defines the many varieties of Japanese ramen. Tokyo eateries specialize in shoyu, or soy-sauce flavored, broths. In Sapporo, it’s miso. But perhaps the most filling soup comes from Hakata, a city known for its signature rich and cloudy stock, made by stewing tonkotsu, or pork bones, on a high flame for up to 24 hours.

In Hong Kong at Hide-Chan Ramen, which opened last month, you’ll find only Hakata-style ramen, which carries the unique broth as well as a special noodle (more on that later).

The restaurant gets its name from owner Hideto Kawahara, who set up his first shop in 1993 in Fukuoka, a town in Japan’s Kyushu prefecture that is known for Hakata-style ramen. Mr. Kawahara also has outlets in Tokyo and New York.

A second-generation ramen maker, Mr. Kawahara is a stickler for details—he even purifies the water used to make the broth to adjust its acidity. Compared with his New York and Japan operations, however, his Hong Kong shop still needs some work. From day to day, the soup base can be inconsistent. On our first visit, the soup was so thickened with lard that it carried an almost floury texture, a bit like drinking watery pancake batter. On a later visit, however, the broth was a smooth and comforting soup.

Still, customers are flocking in. There’s a 15-minute wait for lunch on most days, a telling sign given that many local Japanese restaurants have reported a drop in sales.

To cut through the fatty soup, add some of the traditional toppings for Hakata ramen, which include fresh garlic—whole bulbs are brought to the table with a garlic press so customers can serve themselves—and beni shoga, or strips of pickled red ginger. The spice from the garlic and acidity from the ginger act as perfect foils to the pork flavor. And there’s a whole lot of pork—slices of pork belly and pork shoulder come with the ramen.

There are additional toppings as well. Choose from a list that includes black fungus (for five Hong Kong dollars, or 64 U.S. cents); soft-boiled egg—half (HK$5) or whole egg (HK$10); two pieces of seaweed (HK$15); green onions (HK$10) and bean sprouts (HK$5).

Your noodles, which are the thin and straight, not the curly kind (as is often found in Tokyo-style ramen), are cooked to your preference: soft, medium or hard. And there’s also a choice of soup: White Hide broth, the traditional pork bone soup (HK$75); and, HK$85 each, Black Hide, which comes with a charred garlic and soy sauce, or Red Hide, which comes with a spicy-and-sweet Korean red chili sauce. The Hakata Original Ramen (HK$85)—often sold out—comes with the standard White Hide broth, plus a premium cut of pork neck as your topping.

Tsukemen (HK$90), a different noodle dish, is also on offer. The noodles come separately and are dipped into the soup base.

Tick off your own orders with the paper forms and pencils available on each table. You’ll likely have to reach over a neighbor as the room is packed tight with 30 or so seats.

There’s a small selection of soft drinks, which also include Ramune, a type of carbonated Japanese sweet soda that tastes similar to Sprite. Pork dumplings (HK$48) are the only appetizers; they can come with a variety of sauces, including cheese (HK$5), tarako, or salted cod roe, mayonnaise (HK$10), and green onion mayonnaise (HK$10).

In recent weeks, Mr. Kawahara has also launched efforts to support the earthquake relief in Japan. He led his own team from Fukuoka to the area of Kesennuma in Miyagi prefecture, which was devastated by the quake and tsunami, to provide hot ramen to survivors. Also, on April 1, all sales proceeds at the Hong Kong restaurant earned between 6 p.m. and 11 p.m. were donated to the Hong Kong Red Cross.